Build and export voxel models

Start with a model

Open Voxel Desk from the Renderloom toolbar. Examples offers small original models (Little house, Quiet tree and Pocket robot); New starts an empty grid, and Recents reopens the five voxel models saved on this device. Voxels are colored cells on integer X, Y and Z coordinates. X and Y form the ground plane and Z is up. The volume (for example 16 X × 16 Y × 16 Z) sets the editing bounds, with at most 64 cells per axis and 32,768 occupied cells.

Sculpt slice by slice

The slice editor shows one horizontal layer. Move between layers with the Slice slider or Previous slice and Next slice. Pick a palette color, then choose a tool: Add / replace places or recolors cells, Paint existing only recolors cells that are already filled, and Erase removes them. Drag across the grid to draw. Mirror across X repeats every edit on the opposite side, which is handy for symmetric buildings and characters.

Keyboard users can move the cell cursor with the arrow keys and press Space or Enter to apply the tool. Cell X, Cell Y and Apply at cell do the same with exact numbers; Fill slice and Clear slice work on the whole layer. Add color extends the palette up to 64 opaque colors. Undo and Redo track every edit.

The isometric preview on the right shows the combined shape with fixed face shading. It is an illustration, not a lit render.

Save, import and export

Save project downloads an editable voxel project that keeps every cell and palette color. Open JSON or VOX opens a voxel project or a single-model, opaque VOX 150 file; VOX scene graphs, several models, materials and transparency are rejected with a message instead of being imported partially.

Export offers a transparent isometric SVG or PNG, a single-model VOX 150 file and an OBJ/MTL mesh ZIP. The mesh contains only exposed surfaces with Z up and one unit per voxel; keep the OBJ and MTL files together when you import them elsewhere.

Send it to the scene

Set Voxel size in scene (mm), then choose Send to scene. Adjacent cells of the same color are merged into box solids and appended to the current Renderloom scene as ordinary editable solids. If the result would push the scene past 128 solids, nothing is added and a message explains why — simplify the model or remove scene solids first. The voxel model stays in Voxel Desk for later edits; the scene receives an independent copy. Close Voxel Desk, choose Fit visible model and render a preview.

Tools for scripts and agents

Voxel Height Grid Builder turns rows of whole-number heights into a stepped model, and Voxel Model Inspector validates a voxel project and counts occupied cells, colors and exposed faces. Both return an editable project, an SVG preview and a ZIP with OBJ/MTL and VOX through the tool page, the JSON API and MCP.